Static mac address

Hey. Do you know how to set up the mac address has never changed? The instructions below do not help.

sudo ifconfig eth0 downsudo ifconfig eth0 hw ether 00:11:22:33:44:55
sudo ifconfig eth0 up`

/etc/network/interfaces
iface eth0 inet dhcp
hwaddress ether 08:00:00:00:00:01

sudo apt-get install macchanger
macchanger --mac=01:23:45:67:89:AB eth1

Hi, FYI:

How do I sell a device for a million different people when I do not know how to build a network? May each router disappear after the current has disappeared again to display the ports?

it installs many devices for clients, 128 cctv cameras and it has never been the same as mac address … so it is not possible for it to be a permanent mac address?

Why all Raspberry Pi have a different mac? (Have 30…)

There will have solution for fixed Mac address.

For you question, check the reply for make sure you operate in right way.